Genetic landscape can impact treatment for children with rare, aggressive cancer

Precision medicine may help doctors determine the best treatment options for children with rare, aggressive, and advanced cancers. These findings, from the first 102 patients, were published in JAMA (2015; 10.1001/jama.2015.10080).

Using information from a patient’s entire genome helped suggest personalized treatment options for nearly half of children with cancer, and led to specific treatment changes in a quarter of these patients, according to researchers at the University of Michigan (U-M) Comprehensive Cancer Center and C.S. Mott Children’s Hospital in Ann Arbor.

The study is based on a program implemented at Mott in 2012 called Peds-MiOncoSeq, which includes sequencing the tumor’s DNA and RNA as well as normal DNA from children and young adults with cancer that has relapsed or that is rare.

“We found that for some children with rare, difficult-to-treat, and aggressive cancers, this technology can dramatically change the course of their treatment,” said lead author Rajen Mody, MD, MS, pediatric oncologist at U-M’s C.S. Mott Children’s Hospital.

“We have made significant strides in cancer treatment but for some kids, especially those with metastatic or relapsed disease, even the most advanced, proven therapies have not been able to improve their outcome. Our approach in precision oncology showed its greatest promise in these difficult to treat patients: 80% of our study patients had relapsed or refractory disease, and those are the ones who benefited most from our study.”

Overall, 46% of patients had an actionable finding: a specific genetic anomaly that is the target of an approved or experimental drug; a change in diagnosis; or genetic counseling for inherited cancer risk that could affect the patient or the whole family. Further, 25% of patients went on to receive a study recommended novel therapy, which resulted in 10% of patients achieving a partial or complete remission lasting 6 months or longer.

“We were excited to see an actionable finding in such a substantial percentage of patients, and we think it could potentially be higher over time. These are patients who had exhausted all proven therapeutic options or who had an extremely rare diagnosis. If we can find a clinically actionable event and have a chance to act upon it, we show in this study that it can have a big impact on that patient,” said senior study author Arul Chinnaiyan, MD, PhD, director of the Michigan Center for Translational Pathology.

In addition, researchers also found 10% of patients had an inherited cancer risk potentially impacting multiple family members. Those patients and their families were offered genetic counseling. Four of the nine families had no notable family history to suggest an inherited risk, and they would not otherwise have been referred for genetic counseling.

The cost for sequencing was approximately $6,000 per patient and was covered under the research protocol. Patients in the study did not pay for sequencing. The researchers expect sequencing costs to decrease over time as the technology improves and competition increases. In addition, the researchers needed approximately 7 to 8 weeks to report the sequencing results back to treating physicians and families.

In time, the researchers hope to offer gene sequencing to most, if not all, pediatric cancer patients at Mott. These initial findings have paved the way to expand the program into a more comprehensive pediatric precision oncology program that researchers expect to launch in 2016, which will include offering sequencing to pediatric cancer patients at other hospitals.